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Hilux rear disc brake - AGAIN
Posted: Wed Jul 16, 2008 9:39 pm
by Willy Hilux
I know this has been posted heaps of times, but I'm after some information on hilux front rotors.
I'm wanting to put front lux rotors on the rear behind the axle flange. I got the rotors but the stud holes are 15mm and the axle flange holes are 14mm. I'm using DBA 151 rotors.
On the front axle, are the wheel studs pressed in from behind the rotor??
Does anybody know a part no. for the studs or do I need to coustomise something??
Here's a link of what I'm doing, but it doesn't tell me what parts to use.
http://www.muchadoproductions.com/forum ... conversion
Any help would be great.
Cheers guys.
Posted: Wed Jul 16, 2008 10:03 pm
by Sic Lux
Love the hit the small hammer with the bigger one there goes the old boys eye sight let alone peppered with steel. Wheel studs should be pressed it but you can use the nut reversed (taper out) and a washer also help's the process then just wind them in it's normaly done this way. why not use a floating rotor that just sits over the axle flange will be sitting on a true surface then. Mounted on the rear of the axle might cause to much run out not that it matters as it won't be opperated at highway speeds just a thought
Wheel studs measure them up and see what the front wheel stud lenght is i'd say it'd be close to spot on
Posted: Thu Jul 17, 2008 5:19 am
by Willy Hilux
It's not the lenght I'm worried about, it's the diamater where the spline off the stud is. the holes in the rotor is 15mm while the holes in the axle flange are 14mm.
Posted: Thu Jul 17, 2008 5:00 pm
by 1MadEngineer
Willy Hilux wrote:It's not the lenght I'm worried about, it's the diamater where the spline off the stud is. the holes in the rotor is 15mm while the holes in the axle flange are 14mm.
i know we redrilled one of them but i can't remember the exact size, or what studs we used
i know we got new ones but memory fails me. Dave might remember (when he gets back from europe).
Posted: Thu Jul 17, 2008 5:07 pm
by MissDrew
Why do you want to put the rotor behind the axle flange?
My rear rotors just sit over the top of the studs on the face side of the flange. If I unbolt my calipors I can then just slide the rotor off.
Posted: Thu Jul 17, 2008 6:45 pm
by Sic Lux
Guts wrote:My rear rotors just sit over the top of the studs on the face side of the flange. If I unbolt my calipors I can then just slide the rotor off.
Floating set up like a 80 thats the way i'd be setting it up.
If there 15mm wouldn't you be thinking that front studs would be the right size to fit the rotor, then just drill the axle flange if that fails go down to repco with and measure some up till you find the ones that will fit correctly?
Posted: Thu Jul 17, 2008 8:15 pm
by Willy Hilux
Ii think i've found a toyota stud that will work. It's a N333 - it has a shoulder that is 23.5mm in lenght, the knurled shoulder is 14.3mm in dia and is a total of 51.5mm long.
This means the stud will lock onto the axle flange but will have a total of no more than 1mm play in he rotor holes. The rotor plus the flange thickness is total of 18mm, which the shoulder is 23.5mm. I'll have 5.5mm of shoulder sticking out. I think my 2" wheel spacers should have enough meat in them to take up this.
Next question is - With the studs pulled up tight and the rotor hole being slightly larger than the studs, do you think the rotors will flog about under braking???
I don't think they will. Rember it is a slow speed comp truck not a hwy car.
Posted: Thu Jul 17, 2008 9:55 pm
by ozrunner
Have you given thought to how you are going to get the required fluid volume to two sets of twin piston front rotors.
Posted: Thu Jul 17, 2008 11:08 pm
by locktup4x4
I have a similar setup. I used front wheel studs off a solid axle truck. The shank on the studs is to long so I used a 3/8" spacer to take up the space. I also installed a FJ80 master cylinder.
Jason
Posted: Fri Jul 18, 2008 5:14 am
by Willy Hilux
I'm running a surf mastercylinder or an 80 series cruiser one.
Jason , did you run into the same spot of bother with the two different hole sizes??
cheers for the replies.
Posted: Fri Jul 18, 2008 6:36 am
by locktup4x4
No everything pressed together as it should have. I used 85 solid rotors. The only thing I had to do to the rotor was to machine center out so it would fit over the back side of the axle.
I wouldn't do it this way again. I have broken rear axles and its a pain to change everything over to the new axle on the trail. I shouldn't have any more brakage with chromo rears. Also the caliper dosent float so when I make a sharpe turn I can hear the pads rub on the rotors.
This is an inexpensive way to do it and it works well, but there are good rear disc brake kits on the market.
Jason
Posted: Fri Jul 18, 2008 9:13 am
by 1MadEngineer
locktup4x4 wrote:No everything pressed together as it should have. I used 85 solid rotors. The only thing I had to do to the rotor was to machine center out so it would fit over the back side of the axle.
I wouldn't do it this way again. I have broken rear axles and its a pain to change everything over to the new axle on the trail. I shouldn't have any more brakage with chromo rears. Also the caliper dosent float so when I make a sharpe turn I can hear the pads rub on the rotors.
This is an inexpensive way to do it and it works well, but there are good rear disc brake kits on the market.
Jason
jeez that rings a bell, i am pretty sure thats the same as ours. Except we are using a 45/47 series master which suits the solid rotor calipers better. Very noticeable improvement when using the cutting brakes or air handbrake.
Posted: Fri Jul 18, 2008 9:27 am
by MissDrew
I still can not see why you`d want to go on the inside. Using subaru front calipers is the way to do it, they slide with any movement in the rotor and the handbrake works sweet. Ask ruff how good my handbrake works.
Jasons comment about being a pan when you have to replace rear axles makes sense but its not hard to have spare ones in the shed already done. Or jut run the chromo axle from day 1, a few problems solved from the start.
Posted: Fri Jul 18, 2008 10:31 am
by locktup4x4
I did it because I had all the parts sitting around and it cost nothing for me to do. But to have a spare set you would need the rotors and bearing already on the axles. I keep two axles ready to go in my trailer.
Jason
Posted: Fri Jul 18, 2008 11:05 am
by MissDrew
locktup4x4 wrote:But to have a spare set you would need the rotors and bearing already on the axles.
Jason
Bearing and axle flange yes, rotors no as they slip on over the front of the flange/studs.
I had the outer edge of the flange machined down a bit smaller. Can`t remember if the inner side of the rotor was machined out bigger or not. But even if it was you just take the one your rig and slip it back on the new axle once bolted in place.
Posted: Fri Jul 18, 2008 11:07 am
by 1MadEngineer
Guts wrote:I still can not see why you`d want to go on the inside. Using subaru front calipers is the way to do it, they slide with any movement in the rotor and the handbrake works sweet. Ask ruff how good my handbrake works.
Jasons comment about being a pan when you have to replace rear axles makes sense but its not hard to have spare ones in the shed already done. Or jut run the chromo axle from day 1, a few problems solved from the start.
rotor on the inside to increse the distance to the wheel/rim so that the caliper clears, thats why you still need to run ~6mm spacer.
Posted: Fri Jul 18, 2008 11:14 am
by locktup4x4
The Toyota rotor wont fit over the axle flange, that why it goes on the inside.
My spares are setup with rotors.
Jason
Posted: Fri Jul 18, 2008 11:34 am
by MissDrew
1MadEngineer wrote:
rotor on the inside to increse the distance to the wheel/rim so that the caliper clears, thats why you still need to run ~6mm spacer.
I do not have to run spacers for any clearance issues.
So I still can not see why you go on the inside
Posted: Fri Jul 18, 2008 11:36 am
by MissDrew
locktup4x4 wrote:The Toyota rotor wont fit over the axle flange.
Jason
Correct.
I had the outer diameter of the flange machined down to suit. Can`t remember if the inside of the rotor was also machined out a tad bigger or if it was left as is.
Posted: Fri Jul 18, 2008 12:06 pm
by flyology
Hey Guts, any chance of a picture of your subaru caliper set up? I am using them on the rear of my 60 series, GU discs, 80 series hubs. Just interested to see where the caliper sits on the disc centrally, so I can make some spaces for my brackets........
Posted: Fri Jul 18, 2008 2:01 pm
by ozrunner
I'm also using Suby calipers on my 4Runner but unlike Guts's I'm not entirely happy with the handbrake for road use and will be doing a further swap
I agree with Guts. Have the centre of the discs machined to 106mm and fit them from the outside as per normal.
Posted: Fri Jul 18, 2008 2:34 pm
by flyology
Why are you not happy with the handbrake, how did you set up the cable?
Posted: Fri Jul 18, 2008 3:34 pm
by ozrunner
The cables are fine, all new custom length to suit and relocated accordingly etc.
Even though I also eventually developed a system to double the pull pressure etc they still don't consistently lock the brakes enough to the extent they virtually have zip on even a minor incline let alone a slope.
Might be fine for a light Suby but not a 2300kg 4wd
I've studied them again and again to ascertain what I could do but have now decided to redo the whole deal using a different caliper with a better handbrake setup.
Posted: Fri Jul 18, 2008 4:09 pm
by flyology
Any ideas what caliper you are going to use?
Posted: Fri Jul 18, 2008 4:14 pm
by macca81
hey guts, any chance of a write up onyour setup? i wanna convert to rear disks and have hear about the subi brake, but am yet to actualy see a write up on it...
Posted: Fri Jul 18, 2008 5:27 pm
by ozrunner
flyology wrote:Any ideas what caliper you are going to use?
Yes and I already have a set but have yet to get to fitting them to ascertain their effectivenes but I'm fairly confident they will be more than adequate in all respects
Posted: Fri Jul 18, 2008 5:50 pm
by MissDrew
Ozrunner, did you change the direction the handbrake lever on the calipers pulls? Standard the subi handbrake cable runs up the controll arm. Hilux standard handbrake cable runs across the iff housing. I use a 100% stock standard hilux handbrake cable. All you have to do is turn the lever that comes out of the caliper 90 degs and then grind i flat and drill a hole in it to suit the standard hilux pin.
I`ll pull a rear wheel off the hilux tomorrow and take some pics.
Posted: Fri Jul 18, 2008 6:26 pm
by Willy Hilux
Guts, What rotors did you use? If ya used hilux fronts, you would have had to machine a far bit of the axle flange down to fit the inside of the rotor.
Will your setup still still clear hilux calapirs on 16" rims??
Posted: Fri Jul 18, 2008 6:34 pm
by ozrunner
Guts
The 4Runner has the cable up the control arm so to speak. You can see its general direction in these pics. I had new cables made to suit these calipers etc. Just doesn't give enough "grab" no matter how hard its pulled.
Shame as the calipers give awesome actual braking.
Posted: Fri Jul 18, 2008 6:53 pm
by MissDrew
Ozrunner, wierd as my handbrake is wicked.
Willy I run early hilux front solid rotors
Subaru brumby front calipers.
This setup CLEARS 15 inch rims with NO spacers.
The axle flange was machined down and I think the rotor was machine aswell but can`t remember exactly.
I did this conversion just after the 1st TTC back in 2001.
First off when I did it I didn`t have the caliper lined up correctly with the rotor and it spat pads out once they were worn down to about 50%. I have now fixed that problem and its all sweet.